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  <title>Document</title>
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<body>
  <script>
    let score = parseFloat(prompt("请输入分数："));
    if (score >= 90 && score <= 100) {
      alert("优秀");
    } else if (score >= 70) {
      alert("良好");
    } else if (score >= 60) {
      alert("合格");
    } else {
      alert("不及格");
    }
  </script>
</body>

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